The present invention relates to upper and lower sliding mechanisms for showcases, which are characterized by the fact that a window glass can be stably and smoothly slided without swinging and can be easily safety locked.
As well known, a showcase is used to display articles or the like and can be often seen in department stores or general commercial stores or other public places. However, it happens that when pulling the glass of conventional showcases for accessing articles placed therein, the glass always swings and makes noise and can not be steadily operated. Furthermore, the saw-toothed lock usually used with showcases often gets loose and oblique due to vibration after a period of use, and thus requires adjustment. Therefore, a user always feels inconvenient and bored.
The above-mentioned drawbacks occur for the following reasons:
1. The conventional aluminum lower rail of a showcase is formed with two rail projections 81, as shown in FIG. 8, and the wheel 90 is formed with a lower inward curved surface 91 corresponding to the rail projection 81 so as to roll thereon, wherein the glass 8a or 8b is not closely mounted on the wheel 90 and therefore, when pulled, the glass tends to swing and make noise, and, after worn by the contact with rail for a long time, the wheel will be deformed to deteriorate the stability of rolling and make even louder noise.
As shown in FIG. 10, a conventional aluminum upper rail of a showcase includes a channel bar with substantially M-shaped cross-section, wherein two channels 77 are formed at each side of an intermediated partition 66 for slidably receiving the upper edge of glasses 8a and 8b. It can be seen that the glasses 8a and 8b are not closely fitted into the channel 77 and thereby when pulled or slided, the glasses are easy to swing, make noise and have poor stability.
As shown in FIG. 9, a conventional saw-toothed lock 1 includes a long and flat saw-toothed bar 4 having a n-shaped end 2 to secure a glass thereto with a fastening belt 3. A locking member 5 having a front stopper 6 is slidably mounted on the sawtoothed flat bar 4. A key can be inserted into a key hole 7 of the locking member 5 to disengage with and slide along the saw-toothed flat bar 4. When the stopper 6 is locked, then the other piece of glass may be prevented from moving. When the locking member 5 is slided out of the saw-toothed flat bar 4, the other glass is released from locking, accordingly, and can be pulled open again. However, the fastening bolt 3 often gets loose after several vibrations, making whole saw-toothed lock 1 loose and oblique and therefore require refastening. As a result, quite many troubles are added to the users.